Stapling machine



s. H. HART STAPLING MACHINE '27 /5 Filed August 12, 1920 @f2 f f! 4' l 7 ,u /l

Patented Get. 19, 1926.

SIDNEY IH. HART, OF BROOKLYN, NEW YORK, ASSGNOR TO THE E. H. HOTCHBIISS COMPANY, OF NOE/VIALE, CONNECTICUT, A CORPORATION O1? CONNECTICUT.

STAPLNG MACHINE.

Application filed August 12, 1920. Serial No. 403,004.

Wy invention relates to stapling machines such as are used for stapling sheets of' paper together and it relates to that class ot stapling machines in which the staples are supplied in strip 'Form and in which the staples are individually severed -from the strip. l have herein shown my invention emhodied in the well known Hotchkiss sta pling machine though ity is to loe understood that the invention is not limited to use in that particular machine.

ln machines oi the above type, wherein the staples are cut from a strip individually or as required `'for stapling several diliiculties have heen encountered. One is, that the cutters do not always cut a staple clean from the strip and the staple clogs the inachiue or else it is turned so that it is not n'esented to the paper or other material to which it is to he applied, in the proper position. In some cases the movable cutter or plunger becomes ammed and it is difficult to return it and to get the ammed staple out ot the machine. In other cases the staple is driven down but it is twisted or turned and it iails to properly enter the paper or else it Ytails to enter in the desired position or angle. The alcove diiliculties are due to the failure oit' the cutters to cut the staple clean from the strip or to cut it at the required position.

The diil'iculties referred to are almost certain to occur when the cutters become dull as they do after they have been used for a short time.

Furthermore, it has loeen ditlicult to use very thin stock for the staple strip. The present invention overcomes these diiiicuh ties. lts employment does not complicate the machine nor add materially to its cost, and there is nothing to get out of order. In my copending case Ser. No. 352,021. l showed and described a machine for the same general purpose in which stationary projections supported the projecting end staple during the cutting or shearing operation. ll/Iy present invention is of the same general character hut it is specifically diliferent in that the supporting' member for the projecting or endmost staple comprises a n'ioyahle slide.

Another ditiiculty in former machines is the tendency to clog when the plunger is only partly driven down, and is then allowed to return and is then driven down a second time. In such instances astaple is cut when the plunger is .first forced down hut as the stroke is not complete the staple is not driven into the stock lout remains in the machine. Upon the return stroke oi the plunger `the staple strip is fed forwardly so that on the second downward stroke of the plunger another staple is cut and driven down on the iirst one and one or both staples clog the machine. In the present case the strip is not 'ted forwardly unless the preceding` staple has been driven. It, theretore, the plunger is depressed only part way down and is then allowed to return, the s aple strip is not at this operation 'fed torwardly and when the plunger is depressed again a new staple is not cut oii hut the previously cui'. staple is driven, so that the machine is cleared ready for the neXt operation. This result l accomplish loy timing the 'feeding operation so that it occurs only when the plunger is driven all the way down, and missing a feed if the plunger is only partly depressed.

ln the drawin forming cation,

Figure l is 4a vertical sectional view thiiough a stapling machine embodying my invention,

Figure 2 is an'enlarged sectional view showing the parts for operating and guiding the staples,

Fig'ure 3 is a tace View of the slide for supporting the endmost staple,

Figure 4 is a cross sectional View through the frame and showing the plunger and slide,

Figure 5 is a sectional view showing parts similar to Figure 2 in different positions,

Figure 6 is a detail view of the cam on the plunger and the'part of the feeding device on which it acts, 1

Figure 7 is a horizontal sectional View showing the guide har with a strip of staples in plan, Y

Figure 8 is a view showing parts similar to Figure 5 hut in different positions',

Figure 9 is a sectional view through the plunger and slide, and

Figure l0 isa similar view taken at a part ot this applidifferent point. i

l have shown herein a stapling machine having' most ot its parts corresponding` to machines heretofore made. It comprises a hase l at one end of which there is an titl anvil Q of usual form and in the seat 3 of which the prongs of the staples strike. At the other end of the base there are upstanding.;` ears t between which one end of the cutter bar 5 is pivoted on a pin 6. rlhe frame 7 of the machine surrounds the top and sides of the cutter bar 5 and it is fixed to it by means of the pins S which pass through the frame and cutter bar, so that the former moves with the latter. At the sides. the iframe is spaced from the cutter bar by the rails E) which are interposed between the sides of the frame 7 and parts of Vthe sides ofthe cutter bar 5, and these rails are engaged by the prongs 10 of the uncut strip 11 and they serve to support the strip. The forward edge 12 of the cutter bar forms one of the cutting;r members for cutting` or shearing` the staples from the strip. rlhere is a plunger 13 operating; in a ejuidinpj socket 14 in the frame 7 and it moves at right angles to the plane of the cutter bar The lower edge 15 of this plunger forms the second cutting' or shearing member, and it cooperates with the forward edge 12 of the cutter' bar. rEhe plunger 13 is forced downwardly by hand and its return is effected by means of the compression spring' 1G.

A pawl plate 17 is pivoted at 18 and it is actuated by means of the cam plunger. rl`he shape of thek cam member 19 and the surface of the plate 17 with which it engages are modified as shown.I to time the operations according;l to the requirements of the present device. rl`he plate 17 carries a pawl 2O having' a forked end 21 which straddles the longitudinal rib 22 of the staple strip 11 and the forks engage between theV prongs 10 for the purpose of advancing the strip. There is a detent arm Q3 pivoted on the pin Q4 and it has a forked end 25 which also straddles the rib Q2 and. engages between the prongs 10, being held in contact with the strip by the .sp1-ing; QG.

Each time the plunger -13 goes fully down the pawl plate 17 is rocked backwardly by the shoulder 17a striking' the top 17b of the plate 17; and the forks 21 of the pawl are moved back a distance equal to the distance between two adjacent openings or slots in the staple strip. As the plunger 13 is returned by the spring` 15 the cam block 19 rocks the pawl plate 17 in the opposite direction and the forks 21 move the staple strip forwardly. The detent 2S rests on the strip 11 and it is intended to prevent backward movement thereof.

, As the shoulder 17 does not strike the top 17b of the plate 1.7v until the plunger is near the bottom of its .stroke the pawl Q0 is not moved baclnvardly and therefore it cannot feed the staple strip forwardly unless the plunger is moved substantially to the bottom of its stroke. If, therefore, the

plunger is forced downwardly su'lliciently to sever a staple but not suil'ieiently to drive it, the pawl 2O will miss a feeding;l operation. Upon a subsequent operation of the plunger the previously cut but undriven staple will be driven and the machine will be cleared ready for another operation. rlhus7 one staple is not driven down upon another.

rllhe staple strip 11 is inserted at the back oit the machine between the frame 7 and the cutter bar 5 with the prongs 1() straddlingr this cutter bar and the connecting; piece 22 extending along' the top of the cutter. Generally, the points ot the prongs rest upon the side rails 9. The strip projects beyond the cutting edge 12 of the cutter bar so that one pair of prongs is beyond the cutting; point and so that only the connecting; piece 22 between the first and second pair of prongs is in the line of cutting'. lllhcn the plunger 13 is forced downwardly its edge 15 cooperates vith the edge 1Q to cut or shea the projecting; portion of the strip which then constitutes a stapl rlhe latter is carried down by the bottom end of the plunger and is stapled through the paper in a manner well known in the art.

Thus far 1 have described no means for supporting);` the overhanginer end of the strip to prevent be .ding and without some such means this end is bent down during` the cuttine' or shear-ina operation, causing the troubles referred to above.

The device for supportina' the overhang'- ing; end of the strip during` the shearing' onA eration consists of a slidin n'ien'lber which does not interfere with the driving; of the staple. lhere is a vertical slot il?) in the frai member 7 which opens into the slot in whi the plunger moves and it is preferably wider than the latter slot. A plate slide:` in this slot 28. it comprises upperY forked ends which straddle the projection 31 olf the iilungrer; a cross piece 32, and the lower` forked ends all movable in the slot 255. The forked, lower ends Il?) have an opening' 3L; between them wide enough to admit thi-l staple strip theretln'ough. whereas the lower ends have projections directed tower/l each other to align with the prongs of the staple strip. rlhe plate QS) is preferably arched slightly to press the frame and frio tionally engage or hold in whatever vertical position it is placed. lllhen the plunger is in its uppermost position the plate 2f) is likewise in its uppermost position, the cross piece 32 lyinp; in contact with the cam member 19. l'n this position of the parts the staple strip projects beyond the end of the cutter bar 5 and through the wider opening' 34; of the forked ends The primes of the projecting1 staple of the strip rest against, the rear surfaces of the members 35 of the plate 29. The operator strikes the hand knob 3G a blow to force the plunger down. Duringv ll l lill

rre

the lirst part of the downward stroke et the plunger the plate 29 remains idle and as the cutting edge of the plunger' strikes the top edge ot the projecting staple strip it coop-- erates with the edge l2 0i the cutter bar' and severs the projecting portion of the strip to torm a. staple. The members engage the rear edges ot the projecting prongs 10 while the cutting or shearing operation takes place, so that the projecting portion ot the strip can not bend downwardly and cause an irregular shearing action. The etl'ect is the same as it the projecting end of the str'ip rested on a suppor't. lli, therefore, the shearing members are dull or it they do not hug closely together a clean shearing operation will be performed notwithstanding` this. frs the plunger completes the shearing oper-- ation., or as its lower end registers with the lower ends of the members 35 the upper. forked ends SO ol the plate 29 are struck by the hand linob 36 and from this moment to the end ot the downward stroke the plate 2.- and plunger move in unison. The members` 35 therefore descend with the sever'ed staple, preventing the latter' from turning and jamming. At the end ot the donf'nward stroke oit the plunger' the severed staple will have been driven thr'ouglr the material to b'e stapled and the lower ends ot the prongs will have been clenched upon the anvil 2.

llihen the pressure on the knob ceases, the spring 1G will. return the plunger to its raised position. Then the plunger lirst starts to move upwardly the plate 29 remains idle or' in its lowermost position, held there by friction on the sides oit the groove 28. Vhen the cam projection 19 et the plunger strikes the cross piece 32 oit the plate 29 the latter will then commence to move up with the plunger' and by the time the latter' reaches the end et its upward movement the plate 29 will have been raised sutliciently to bring the members 35 into position to support the prongs of the overhanging portion. ot the staple strip. The pawl 2O iteeds the staple strip forwardlj7 while the plate 29 is moving upwardly, so that the leading end is advanced through the wider opening 34 in this plate. The feeding voperation is completed in time tor' the members 35 to r'ise up behind the prongs of the projecting part ot the strip. rllhese operations are repeated over' and over again.

The members 35 form a rigid backing tor the prongs ot the staple strip during the severing operation and they follow down with the severed staple to prevent the latter trom turning during` the driving. The sliding plate is a simple member to manufacture as it may be stamped or blanked trom sheet metal at a low cost.

Having describedv my invention, what I claim is:

l. A stapling machine in which individual staples are cut from a strip comprising a trame, a critter' bar, means tor advancing the staple strip over' the cutter bar to project the end tlrereoll beyond the critter' bar to be sev-- ered, a slide movable at right angles to the cutter bar tor maintaining the projecting end ot the staple strip in horizontal position during the cutting operation, and a plunger' moving at right angles to said critter' bar and co-operating therewith to sever the` staple, said frame having a raceway for guiding said plunger and having a separate race 'ay for' guiding said slide.

2` A stapling machine in which individual staples ar'e cut trom a strip, comprising a trame, a cutter bar', means for yadvancing the staple strip over the critter' bar to project the end thereof beyond the critter' bar' to sever' it, a plunger` moving at right angles to and cooperating with said cutter' bar to sever' the staple, and a slide tor' engaging the projecting staple, said slide lying against one face or" the plunger and movable parallel therewith, said trarne having a raceway for guiding the plunger and having a separate racewa-y for' guiding said slide.

Signed at the city, county and State ot New York, this 4th day of August, 1920.

SIDNEY H. HART. 

